1. Field of the Invention
The present invention, in general relates to removing caffeine from a foodstuff and, more particularly, to a method for removing a portion of the caffeine from an aqueous solution, such as an extract of a vegetable material, for example; a coffee or a tea, by exposure of the aqueous solution to a molecularly imprinted polymer.
The deleterious effects of excessive caffeine consumption are only partially understood at present. However, what is known is sufficient to generally determine and conclude that caffeine is potentially detrimental when consumed in excess.
For certain individuals, even a small intake of caffeine increases certain health risks and they, therefore, are required to either limit or in some circumstances, entirely eliminate their intake of caffeine.
Methods for decaffeinating foodstuffs are generally well known. For example, decaffeinated coffees have long been on the market. However, there are a few significant problems inherent with currently known decaffeination processes.
First, the majority of these processes use toxic organic solvents as part of the decaffeination process. This is a fact not generally well advertised for obvious reasons. If it were well known, confidence in the use of such decaffeinated products would decline and their consumption would similarly decline.
This is because most people who consume decaffeinated foodstuffs and beverages in particular, do so for health-conscious reasons. The possibility that they may instead be consuming unknown amounts of other potentially harmful substances that are used in, or are a product of the decaffeination process, is not likely to well received by such health-conscious individuals.
Also, the efficacy of current decaffeination methods varies considerably with the method. While some are capable of removing substantial percentages of caffeine, other methods are not as effective.
Those methods that are effective tend to be broad based in their approach, removing a wide variety of organic compounds not intended to be removed from the foodstuff. This can have a deleterious effect upon the taste of the foodstuff by removing organic compounds that normally give the foodstuff its unique character and flavor.
Another well known problem inherent, as was briefly mentioned hereinabove with certain decaffeination processes, is that they may affect the taste of the foodstuff. While some gains have recently been made in this regard, most consumers feel that decaffeinated products taste worse, perhaps even far worse, than their caffeine containing counterparts. This problem is so acute that many consumers who are advised to drink decaffeinated coffee, for example, quit drinking coffee entirely rather than endure a taste which they feel is vastly inferior to that which they have previously experienced.
One of the reasons for this is that the chemicals used to decaffeinate the foodstuff may themselves have a taste of their own that lingers in various amounts thereby coloring the taste of the decaffeinated product. This is confirmed by many consumers who state that decaffeinated coffee, for example, has a "chemical taste" that is unappealing.
And as mentioned hereinabove, the non-specific removal of organic compounds from the foodstuff also tends to remove certain of the ingredients that provide it with a delicate or otherwise characteristic flavor. Therefore, after decaffeination has occurred, the taste appeal may no longer remain. Consequently, market share will inevitably be less with a poor tasting decaffeinated foodstuff, in particular with a coffee or tea, that it would if the taste were minimally affected or better yet, unaffected except for that caused directly by the removal of the caffeine.
Another concern is cost. Decaffeinated products can cost more than untreated products. This is due to the time and labor involved in the decaffeination process as well as to the cost of materials used, such as chemicals. It is, of course, desirable to lessen the cost to decaffeinate a product, thereby making it more affordable for the general public to consume.
There is another disadvantage that the consumer of decaffeinated beverages faces and that is limited range of selection. For example, a coffee drinker who does not restrict his or her caffeine intake may purchase a great many varieties of coffee beans or various combination blends of these beans at most coffee roasting houses. However, if he or she wishes to consume a decaffeinated coffee, only a very few selections are likely to be available.
Furthermore, the use of organic solvents to decaffeinate coffees and teas pose environmental hazards as well. A very large quantity of organic solvents are presently being used for decaffeination purposes. These organic solvents are pollutants that can adversely affect the aquifer or otherwise contaminate the ground, either as waste products or if carelessly handled. They also pose a substantial risk to employees.
Also, some of the other processes presently used to decaffeinate vegetable materials expend considerable quantities of energy as the vegetable materials are repeatedly exposed to steam, for example.
While the deleterious environmental impacts from organic solvents and energy consumption may, at first seem insignificant, they are substantial once the true magnitude is understood. The quantity is so large that, literally, mountains of coffees are decaffeinated annually and the quantities of organic solvents that are used and eventually released into the environment as pollutants are enormous as is the energy that is consumed. Therefore, from the environmental perspective a process for decaffeinating aqueous solutions that conserves energy and substantially lessens the use of organic solvents is desirable.
Accordingly, there exists today a need for a method and product for decaffeinating an aqueous solution, such as an extract of a vegetable foodstuff that is safe to use, does not introduce new and potentially unpleasant tastes, can be used with a variety of beverages that contain caffeine, and is effective. Clearly, such a method would be useful and especially desirable.
2. Description of Prior Art
Decaffeination methods and devices for decaffeinating coffee are, in general, known. For example, the following patents describe various types of these devices:
U.S. Pat. No. 4,465,699 to Pagliaro, Aug. 14, 1984; and
U.S. Pat. No. 4,922,812 to Schweinfurth, May 8, 1990.
Methods involving molecular imprinting to form synthetic enzymes and synthetic antibodies are also, in general, known. For example the following patents describe various types of these devices:
U.S. Pat. No. 4,111,863 to Wulff, Sep. 5, 1978; and
U.S. Pat. No. 5,110,833 to Mosbach, May 5, 1992.
While the structural arrangements of the above described devices and methods, at first appearance, have similarities with the present invention, they differ in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior devices and methods.